With the rapid progress of information technologies in recent years, information products like cell phones, computers and personal digital assistant (PDA) are very common. These products satisfy various requirements of people, and make people become more and more dependent on information products. Nowadays, the information products have become an important part of people's life.
With constantly development of electronic technologies and manufacturing techniques, functionalities of information products are correspondingly innovated as well. More and more electronic apparatuses are disposed with a touch screen, such that users can operate the electronic apparatus via the touch screen. For example, users may perform operations by touching the touch screens with fingers.